An introduction to the science & practice of photography (1891)
Jones, H. Chapman (Henry Chapman), 1854- · London : Iliffe & Son · leaf 75
he something that moves in this way. It has been named before it is born — the " luminiferous ether." Although the nature of light is a matter of conjecture, we know in many cases what its effects are, and how to control those effects. We know that light travels from a luminous object, and the rate… … Fig. :.— A, luminous surface; B, opaque object; C, screen upon which the shadow is cast. Light travels through homogeneous media in straight lines, and, therefore, any opaque substance introduced into the path of light that emanates from a point produces a sharply-defined shadow. But it is…
Photography
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.
